1.服务端的代码：

package Day1209;

import java.io.IOException;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

public class Server {
    //服务端
    public static void testServer() {
        System.out.println("等待客户端连接...");
        //null=赋初值(开辟内容空间)
        ServerSocket ss = null;//创建一个socket服务端,用于接受socket请求
        Scanner keybordInput = null;//键盘输入流 Scanner:扫描器
        Scanner socketInput = null;//网络输入流
        PrintWriter socketOutput = null;//网络输出流
        try {
            //发布一个端口
            ss = new ServerSocket(8083);
            //创建一个接收链接客户端的对象
            Socket socket = ss.accept();
            System.out.println(socket.getInetAddress()+"已成功连接到此台服务器上.");
            //字段输出流 
            socketOutput = new PrintWriter(socket.getOutputStream());
            socketOutput.println("已成功连接到远程服务器！" + "\t" + "请您先发言。");
            socketOutput.flush();//把打印的内容"冲"出去,即是发出去
            keybordInput = new Scanner(System.in);//扫描系统(键盘)
            socketInput = new Scanner(socket.getInputStream());//声明一个网络输入
             // 阻塞等待客户端发送消息过来
            while(socketInput.hasNextLine()){//设定循环,当网络输入流有下一行时执行循环
                String indata = socketInput.nextLine();//每次读取网络输入流数据的下一行数据
                System.out.println("客户端：" + indata);//打印
                System.out.print("我(服务端)：");//站位显示效果
                String keyborddata = keybordInput.nextLine();//键盘输入的下一行数据读取
                socketOutput.println(keyborddata);//打印键盘输入数据流数据
                socketOutput.flush();//发送字节数据流
            }
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            socketOutput.close();
            keybordInput.close();
            socketInput.close();
            try {
                ss.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        testServer();
    }
}

2.客户端的代码:

package Day1209;

import java.io.IOException;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;

public class Client {
    public static void testClient() {
        System.out.println("正在向服务器请求连接...");
        //socket：网络链接对象，即TCP封装成的对象
        Socket socket = null;
        //键盘输入流
        Scanner keybordInput = null;
        //网络输入流
        Scanner socketInput = null;
        //网络输出流
        PrintWriter socketOutput = null;
        try {
            socket = new Socket("127.0.0.1",8083);
            socketInput = new Scanner(socket.getInputStream());
            System.out.println(socketInput.nextLine());
            socketOutput = new PrintWriter(socket.getOutputStream());
            //先读取键盘录入方可向服务端发送消息
            System.out.print("我(客户端)：");
            keybordInput = new Scanner(System.in);
            while (keybordInput.hasNextLine()) {
                  //键盘输入内容，写到服务端的的控制台
                String keyborddata = keybordInput.nextLine();
                socketOutput.println(keyborddata);
                socketOutput.flush();
                //阻塞等待接收服务端的消息
                String indata = socketInput.nextLine();
                System.out.println("我(服务端)"+indata);
                System.out.print("我(客户端):");
            }
        } catch (UnknownHostException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally {
            keybordInput.close();
            socketOutput.close();
            socketInput.close();
            try {
                socket.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
    }
    public static void main(String[] args) {
        testClient();
    }
}